Abstract: A photovoltaic solar cell module comprises a plurality of bifacial solar cells and electrical conductors. Each bifacial solar cell comprises a plurality of bus-bar contacts. A phosphorous silicon glass layer is formed on one side of the bifacial cell by phosphorous diffusion, and a boron silicon glass layer is formed on the other side of the bifacial cell by boron diffusion. The phosphorous diffusion and the boron diffusion are conducted by a face-to-face diffusion method. The combination of the two gettering methods substantially increases the minority carrier life time of the bifacial solar cell.